Photographic-printing apparatus



w. c. HUEBNER PHOTOGRAPHIC PRINTING APPARATUS Oi-iginal Filed Fb. 27,191 s She'ets-Sheet 1 March 16 1926. 1 1,576,511

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March-16,1926; 1,576,511

. W. C. HUEBNER VPHOTOGRA PHI'C PRI NTING APPQRATU S drizinal Filed Feb.27, 1919.. 5 Sheets-Sheet 5 Patented Mar. 16, 1926. i v UNITED STATES v1,576,511 PATENTFOFFICE.

WILLIAM C. HUEBNER, OF BUFFALO, NEW YORK, ASSIGNOR T iHUEBNER-BIJEISTEINPATENTS COMPANY, OF BUFFALO, NEW YORK.

PHOTOGRAPHIC-PRINTING APPARATUS.

Original application filed February 27, 1919, Serial No. 279,493.Divided and this application filed March a citizen of the United States,

in the county of Erie and State of To' all whom it may concern: Be itknown that I, WILLIAM C. HUEBNER residing at Buffalo, New York, haveinvented a new and useful Improvement in -Photographic- PrintingApparatus, of which the following is a specification.

This invention relates to holders for the negatives or' transparentprinting plates used in photographic contact printing or projectioncomposing apparatus and other apparatus used in connection withphotographic plate production and more particularly to means for maskingsuch negatives and for preventing the leakage of light through theborder portions thereof. Such photographic printing apparatus areintended for photographing any desired numher of like.or' difl'e'rentprints in any required predetermined and registered position andrelative arrangement upon the sensitized surfaces of metal press platesor glass .plates which are afterwards suitably finished and used inmechanical printing presses or photographic apparatus for printmgin oneor more colors. This application is a-division of my application forUnited States Patent No. 1,413,- 406 of April 18, 1922.

Heretofore it has been customary to place masks of various material overthe edges of the transparent printing plate and the glass supportingplate to-prevent the leakage of light to the sensitized surface. But theuse of such masks is objectionable because of the time required to placethem in 1 position and the delay in the output of the hotogra-phicrintin apparatus. Such iiiasks, furthernlbre, ar easily displaced andoften result in spoiling the prints during exposure because a displacedmask allows light action in the wrong place on the sensitized surface.The masks also prevent close contact betweenglas's or rigid printing andprint receiving plates, leaving a space between the plates so that lightcan leak around the various printing units, which results/ in veryinferior work, or spoiling the plates.

The objects of this invention are to providemeans which will prevent theleakage of light through the border portions of the transparent printing plate and will avoid 20,1922. Serial No. 545,074.

the above mentioned inconveniences and trouble incident to the use ofmasks; also to provide desirable means for masking or covering a portionof the printing plate so as to enable a print to be made from a portiononly of the plate, or from one or more of a plurality of images on theplate and at the same time ensure proper contact between the printingand print-receiving surfaces; also toprovide the holder'with means forretaining a flexible transparent printing plate or film thereon andmeans for masking a portion of-such flexible printing plate or film soas to enable a print to be made from a portion only of such flexibleprinting plate on a glass or rigid print-receiving plate and' to ensureperfect contact between all portions of the printing and print-receivingsurfaces. i

In the accompanying drawings:

Fig. l is a plan or face view of a printing plate holder embodying theinvention and showing a printing plate in position thereon.

Fig. 2 is an edge elevation of the holder. Fig. 3 is a perspective viewof one corner of the transparent supporting plate for the printingplate.

Fig. 4 is an enlarged section showing one of the securing devices forthe printing and supporting plates.

Fig. 5 is a plan or face view showing modified securing means for theprinting plate holder and also showing means for masking a portion ofthe printing plate.-

Fig. 6 is a sectional elevation thereof on line-6-6, Fig. 5.'

Fig. 7 is a sectional view of one of the attaching devices for themasks.

Fig. 8 is a view similar to Fig. 5, showing the holder provided withmeans for securing plate provided with a central opening 1 oppositewhich the printing plate is arranged so as to be illuminated y lightpassing through the opening. 2 indicates a strong glass orrigid,transparent supporting plate which is secured on the holder overor bridging the opening -1 therein and supports the printing plate. Theprinting plate and supporting plate are secured on the holder B bysecuring devices of any suit- ,able sort and which are arranged at aplube placed against and contact with the outer face of the printingplate throughout the extent thereofand pro ect beyond the edges of theprinting plate without coming in contact with the securing. devices orother parts of the holder. The latter cannot therefore interfere withthe complete and perfect contact of the printing plate with aprint-receiving surface which may project beyond the edges of theprinting plate.

The opposite faces and the edges of the marginal portions of thesupporting plate 2 are covered with a thin, opaque coating or paint 12of any suitable sort adapted to prevent the passage of light through thecoated portions of the plate, and the margi nal portions of the negativeor transparent printing late A are similarly covered with a thin, opaquepaint or coating 13. The opaque border, 12 of the supporting plateextends inwardly from the edges of the plate to or beyond the edges ofthe negative and the opaqueborder 13 of the negative extends to themargin of the picture or subject on the printing plate. In this way,light is effectually prevented from leaking through the edges ormarginal portions of the surfaces of the printing andsupportingflplates. The opaque coatings are thin enough not to preventthe proper contact of the printing plate'against the supporting plateand against the press plate or printreceiving surface. These bordercoatings take the place ofand serve the function of the stripsofmaterial or masks which have heretofore been used and are much moredesirable in that they eliminate the inconvenience and trouble incidentto placing and securing the mask strips in place, they cannot bedisplaced and they. also insure a better contact of the printing platewith the supporting plate and print-receiving surface. They also coverthe edges of. the plates'which are not properly covered by theseparate-piece masks or strips 33 and 34, Figs. 5 and 6, indicate thinmasks or covering strips of paper, or-other suitable thin, opaquematerial, which are adapted to be placed crosswise of each other overthe face of the printingplate and thus cover a greater-or less portionof the face of the plate, depending upon the width of the mask strips.Each of these mask strlps is preferably held at its opposite ends inspring or-other clips 35, of any suitable construction, which areconnected by suitable elastic webs 36 to hooks or fastening devices 37adapted to be engaged with rods 38 attached to the printing plate holderbeyond the edges of the printing plate. These attaching rods 38 can besecured to the plate holder, preferably detachably, by any suitablemeans, such as short posts 39 through which the rods extend and whichare removably retained by friction in holes 40 in the corners of theplate holder. This construction enables the mask strips and theirattaching devices to be readily placed in position on the plate holderover the printing plate when they are desired for use and to be removedwhen they are not needed. The

masks are made of material which is thin enough not to prevent a propercontact of the exposed portion of the printing plate with a flexible,,metal print-receiving plate. It should be understood that thisprint-receiving plate is pressed against the transparent printing plateby a suitable pressure device (not shown), located at the rear side ofthe print-receiving plate opposite the portion of the printing platewhich is left uncovered by the masks. As shown b Fig.

6, the attaching devices for the mas s, as

well as all other parts of the plate holder and its supports, arelocated below or back from the plane of the outer face of the printplate so as not to prevent the proper contact of the printing plate witha printreceiving surface which may project beyond the edges of theprinting plate over the attaching'devices or other parts of the holderor supports.

Figs. 8 and 9 show the printing plate holder equipped with means forsecuring a thin, flexible, transparent printing plate or film 41, andmasking film or sheet 42 over the glass or rigid plate A. As shown, thetransparent printing film 41 has secured to two opposite edges, parallelattaching bars 43, each provided with a pair of headed studs 44, adaptedto enter undercut transverse slots 45 in the screw-operated securingblocks 46 for the glass plate A. By slipping the studs 44 into the slotsof the securing blocks and moving these blocks by means of theiroperating screws, the thin film canbe stretched taut over the face ofthe glassplate A. This transparent printing film is then hacked and heldfrom deflection by the glass plate A and can be used for makingphotographic prints on either a flexible or rigid, print-receiving plateor surface. The mask or cover film 42 is a. thin, transparent film whichextends over the face of the glass plate A between the same and theprinting film 41. This mask filmis stretched and secured on the holderin a manner similar to the printing film by attachingbars47 secured tothe four edges of the mask film and provided with headed studs 48adaptedto be. engaged in transverse, undercut slots in the securinglocated so as to cover or blank out any desired portion of the printingfilm. The light cannot pass through this opaque portion so that only,theportions of the image or images which are not covered by the opaquecoating will be printed. Since the mask or cover film underlies theprinting film throughout the entire area of the glass or rigid plate A,the outer surface of the printing film will occupy the. same planethroughout and can be placed in perfect contact throughout its entireprinting area with a glassv or rigid print-receiving surface, thusinsuring a perfectjprint on such a glass or rigid print-receivingsurface. Perfect prints can, therefore, be made on glass plates or otherrigid print-receiving surfaces which would not be possible if maskstrips or pieces were used which covered only a portion of the printingfilm because such strips or pieces would prevent an intimate contact ofportions of the printing and print-receiving surfaces, thus leaving aspace which would permit leakage of light sulficient to make animperfect print.

It is intended to use the holders and masks described in photographiccontact printing and projecting composing apparatus as well as otherapparatus used in connection with photographic plate production. q Iclaim as my invention:

L The combination of a printing plate having a transparent supportingplate secured thereon, and means for securing a transparent printingplate on said supporting plate, said supporting plate having an opaqueborder which extends to the edges of said printing plate to prevent theleakage of light around the printing plate.

*2. The combination of a printing plate f holder having a transparentsupportingplate secured'thereon, and means for securing a transparentprinting plate on said supporting plate, the marginal portions of saidsupporting plate which extend beyond the edges of the printing platehaving thereon an opaque coating to prevent a'leakage of light throughsaid marginal portions.

3. The combination of a printing plate holder provided with atransparentsupporting plate, and means for securing a transparent printing plate onsaid supporting plate, the marginal portions of said supporting andprinting plates being covered by meeting opaque coatings to prevent theleakage of light through said marginal portions.

4. The combination of a printing plate means forsecuring a transparentprinting,

plate on said holder in a position bridging said opening, a thinflexible mask arranged in masking relation to said printing plate toprevent the passage of light through a portion of said plate and enableprinting from a portion only of the plate, and attaching devices forsaid mask constructed to draw the mask taut on the holder and detachablysecured to said plate'holder whereby the mask and attaching devices canbe secured on and removed from said plate holder.

6.. The combination ofa holder having a light opening therethrough andprovided with means for securing a rigid transparent plate on saidholder in a position bridging late overlyin said rigid plate, atranspargnt mask localied between said flexible and rigid plates andhaving an, opaque portion which prevents passage of light through theoverlying portion of the printing plate, and means for securing saidflexible plate and mask in place. 1

7. The comb' ationof a transparent sup-' porting plate, a flexibletransparent printing plate overlying said supporting plate, atransparent mask overlying said supporting plate' between the sameandsaid. flexible printing plate and backing said flexible plate throughoutits operative portion, said mask having an opaque portion which preventspassage of light through'the overlying portion of said printing plate,and means for securing said printing plate and mask in position oversaid supporting plate.

. 8. The combinationof a holder having a light opening therethrough andprovided with means for securing a rigidtranspa'rent plate on saidholder in a position bridging said opening, a flexible transparentprinting plate overlying said rigid plate, a-tran'sparent mask locatedbetween said flexible and rigid plates and having an opa ue portionwhich prevents passage of light through the no I overlying portion ofthe printing plate, and means for 'removably securing and stretchingsaid flexible plate and mask on said holder.

9. The combination of a printing plate holder having a light openingtherethrough, means for securing a transparent printing plate on saidholder in a position bridging said opening, a thin mask arranged inmasking relation to said printing plate to prevent the passage of lightthrough a portion of said plate and enable printing from a portion onlyof said plate, and attaching desaid plate and enable. printing from aportion onlyof said plate, and attaching devices on said holder forsecuring said mask thereon, said printing plate securing means and saimask attaching devices being arranged on said holder below the outerfaces of said plate and mask.

11. The combination of a holder having an opening therethrough andprovided with means for securing a rigid transparent plate on saidholder i115 a position bridging said opening, a flexible transparentprinting plate overlying said rigid plate, a transparent mask locatedbetween said flexible and rigid plates and having an opaque portionwhich prevents passage of light through the overlying portion of theprinting plate, and

means on said holder for securing said flexi ble plate and mask inplace, said securing means being arranged below the printing surface ofsaid flexible plate.

WILLIAM HUEBNER.

